Circumference of Circles

Front

What is the formula to calculate the circumference of a circle?

Back

Circumference = 2 × π × radius or Circumference = π × diameter.

Front

If the diameter of a circle is 10 cm, what is its circumference?

Back

Circumference = π × diameter = 3.14 × 10 cm = 31.4 cm.

Front

What is the relationship between diameter and radius?

Back

The diameter is twice the length of the radius. Diameter = 2 × radius.

Front

What is the value of π (Pi) commonly used in calculations?

Back

π (Pi) is approximately 3.14.

Front

If a circle has a radius of 7 inches, what is its circumference?

Back

Circumference = 2 × π × radius = 2 × 3.14 × 7 = 43.96 inches.

Front

What does circumference represent in a circle?

Back

Circumference is the distance around the circle.

Front

How do you find the radius if you know the circumference?

Back

Radius = Circumference / (2 × π).

Front

What is the circumference of a circle with a radius of 4 cm?

Back

Circumference = 2 × π × radius = 2 × 3.14 × 4 = 25.12 cm.

Front

If a wheel has a circumference of 60 cm, what is its diameter?

Back

Diameter = Circumference / π = 60 cm / 3.14 ≈ 19.1 cm.

Front

What is the circumference of a circle with a diameter of 12 m?

Back

Circumference = π × diameter = 3.14 × 12 m = 37.68 m.